Wow, you’re all very lucky to ride in such beautiful surroundings. Here in the Netherlands it’s all flat with many dikes and wind. The picture below, that I’ve taken myself from a small Piper airplane, shows my cycling area. At the bottom you see the “old land” and a bridge that ends up in the “new land”, wich is a polder (Flevoland) protected by dikes. I will probably ride there today.
A couple of times a year I go to the south east of the Netherlands where we have some hills, you might have seen some of them when watching the Amstel Gold Race.